We discovered a fan heater in the server room that someone had obviously plugged in because they were cold. We never discovered the culprit (had a few ideas though) but sent round an email to the entire company stressing that people should not plug anything especially heaters into "IT power sockets".
A few days later I picked up a call from a very timid sounding lady I'll call "Jane" who worked at a branch office. She'd recently reorganised her office to get her out of the stream of cold air coming in from the leaky window. Apparently Jane had moved her desk from one side of her room to the other. She wanted to know how we found out that she'd plugged her heater into the socket the computer was previously in. Jane also wanted to know if she could actually use her heater again as the radiator in her room still didn't work and it was very cold.
After determining that this wasn't a wind up I asked what had happened. Jane told me that she'd finished moving her desk and then plugging her computer equipment back in. Having checked that everything worked she'd plugged in the fan heater and then gone to get a coffee.
When she got back there was an email sent to everyone not to plug heaters into IT sockets.
Genuinely worried that we had some super spy capability/hidden cameras for detecting the power use…….she'd unplugged her heater immediately.
Jane had then spent the next few days in a very cold office with her coat on because she was scared of a telling off by IT.
I explained that she'd been a victim of an unfortunate coincidence and so long as the heater wasn't:
a) Pointing at the computer
and
b) Plugged into an extension strip
Then we didn't care what she did to heat her room in the offices.